Gearing.



N. P. FRASER.

GEARING.

APPLICATION rum) 11111329, 1909.

955,858. Patented Apr. 26, 1910.

6 J5 Z1 Q J0 34 q 9 {A J2 Z I NORMAN PETO FRASER, OF CARSONVILLE,MICHIGAN.

GEARING.

Specification of Letters Patent.

Patented Apr. 26. 1910.

Application filed June 29, 1909. Serial No. 505,005.

To all whom it may concern:

Be it known that I, NORMAN I. F msnn, a citizen of the United States,residing at Oarsonville, in the county of Sanilac and State of Michiganhave invented a new and useful Gearing, of which the following is aspecification.

This invention relates to steering devices for motor vehicles in which aworm gearing is employed for transmitting the motion of the steeringshaft to the steering mechanism.

The object of the invention is to provide improved means forautomatically taking up wear of the gears, and with this object in view,the invent-ion consists in the novel construction and arrangement ofparts to he hereinafter described and claimed, reference being had tothe drawing hereto annexed in which,

Figure 1 is a side elevation of the invention. Fig. 2 is a centrallongitudinal section. Fig. 3 is a plan view. Figs. 1 and 5 areperspective views showing the two parts forming the support for thegearing. Figs. 6 and 7 are perspective views of parts forming the Wormwheel.

Referring to the drawings, 8 denotes a pair of plates having one oftheir edges connectedby a cross bar 9. At their opposite edges, theplates are connected by spaced upper and lower solid portions 10 and 11having bearing openings in which the steering shaft 12 is supported andbetween which said shaft carries the endless screw or worm 13, mountedon the shaft to turn therewith. Overlapping the plates 8 is a pair ofplates 14 connected at their outer edges by cross bars 15 and 16, thelatter fitting on the cross bar 9. A portion of the plates 14: abutsagainst a shoulder 17 on the outer surface of the plates 8. In the upperedges of the plates '8 are notches 18 which are entered by tongues 19projecting from the corresponding edges of the plates 14.. The plates 8and 1 1 are fastened together by a transverse bolt 20.

In the overlapping portions of the plates 8 and 14;, are bearingopenings in which the shaft 21 of a worm wheel to be presentlydescribed, is supported. These openings are formed by means of recesses22 in the edges of the plates 8 and 14. A portion of the recesses of theplates 22 is semi-circular, and said plates are thickened at this pointas indicated at 23 to make a bearing of sufficient length to properlysupport the shaft 21. The recesses 22 in the plates 1 1 aresemicircular, and are so located that they coincide with the similarportions of the recesses of the plates 8. The plates 1 1 adjacent totheir recesses are also thickened for the same purpose as the plates 8,and the recessed edge of said plate 1 1 abuts against the shoulderformed by the thickened portion 23 of the plates 8.

By the construction thus described a simple and easily assembled supportfor the shafts 12 and 21 is had. In practice the support will beinclosed in a suitable housing which, for the sake of clearness, has notbeen shown.

The worm wheel hereinbefore referred'to comprises a base 2 1 from whichprojects a pair of spaced parallel sector plates 25 provided with hubs26 through which the shaft 21 passes, and to which shaft said plates arekeyed or otherwise rigidly secured. On the arcuate edges of the platesare teeth 27 which are in mesh with the thread of the worm 13. Atopposite ends of the base 21 are outstanding flanges 28 havingscrewthreaded apertures 29.

Between the plates 25 is a segmental plate 30 having teeth 31 which arealso in mesh with the thread of the worm 13. This plate 30 is looselymounted on the shaft 21, it being provided with an opening 32 for thispurpose through which the shaft extends. The teeth 31 coincide with theteeth 27, the three plates thus forming a worm segment which is in meshwith the worm 13.

To one of the flanges 28 is secured a. flat spring 33, the free end ofwhich presses against the chord of the segment 30, and tends to turn thesegment on the shaft 21. This turning movement is limited by a stopcomprising a screw 34 threaded through one of the apertures 29. Saidscrew also passes through the spring 33 and serves to secure the same.Each end of the screw is provided with a lock nut 35, for securelyholding the same at adjustment. One of the lock nuts is screwed againstthe spring and also serves to regulate the tension thereof.

By the hereindescribed sectional worm wheel, all wear is automaticallytaken up. Inasmuch as in steering devices employing a worm gearing thereis more wear at the point where the parts are in straight ahead positionthan at any other point, it Will be r the worm,

evident that when the gears are turned to make a corner, the high orunworn parts will be in engagement, the spring permitting the segment toyield and thus permit the gear to work snugly without binding. Byreversing the position of the spring wear 011 the other side of the gearis taken up. Two apertures 29 are provided to permit the reversal of thespring to be readily made. The spring can be adjusted so that it willhave tension on the gear when first set up, if so desired, and by sodoing it'will automatically take up wear; or, it can be left merely toset the gear snug at thelow point.

The invention herein described is not limited to steering gears, but maybe successfully employed in connection with other mechanism in which aworm gear is used. It will also be understood that various changes inthe structural details may be resorted to without a departure from theinvention.

That is claimed is V 1. The combination with a worm, of a gear in meshtherewith, said gear comprising spaced toothed plates in mesh with theworm, and a yielding toothed plate mounted between said plates and inmesh with the worm.

2. The combination with a worm, of a shaft, a gear on the shaft in meshwith the worm, said gear comprising a pair of spaced toothed plates faston the shaft, and in mesh with the worm, a toothed plate loose on theshaft between the aforesaid plates and in mesh with the worm, andyielding means for turning the intermediate plate on the shaftindependent of the first mentioned plates.

8. The combination with a worm, of a shaft, and a gear on the shaft inmesh with said gear comprising a pair of spaced toothed plates fast onthe shaft, and in mesh with the worm, a spring carried by on the shaftbetween the aforesaid plates and in mesh with the worm, a spring carriedby the first mentioned plate and engageable with the intermediate plateforturning the same on the shaft, and a stop for limiting the turningmovement of said plate.

4:- The combination with a worm, of a shaft, and a gear on the shaft inmesh with the worm, said gear comprising a pair of spaced toothed sectorplates fast on the shaft and in mesh with the worm, and said plate beingprovided with a base portion having outstanding flanges, a toothedsegmental plate loosely mounted on the shaft between the aforesaidplates, and in mesh with the worm, a spring secured to the aforesaidbase and engageable at its free end with the segmental plate for turningthe same on the shaft, and a stop for limitingthe said turning movementof the plate.

5. The combination of a pair of plates having connecting portions at oneof their edges which are spaced and provided with hearing openings, ashaft mounted in said openings, the faces of said plates havingshoulders, and a pair of plates overlapping said plates and abutting onsaid shoulders, means for securing said plates together, said plateshaving mounted in the openings, and gearing between the shafts.

6. The combination of a pair of plates having connecting portions at oneof their edges which are spaced and provided with bearing openings, ingnotches in one of their edges, a shaft mounted in the aforesaidopenings, the faces of said plates having shoulders, a pair of plates onsaid shoulders, and having tongues entering the aforesaid notches, meansfor se-' curing the plates together, said plates having transverseopenings, a shaft mounted inthe openings, and gearing between theshafts@ In testimony that I claim the foregoing as my own, I have heretoaflixed my signature in the presence of two witnesses.

NORMAN PETO FRASER.

Witnesses:

G. A. H. DYSART, G. C. F RASER.

transverse openings, a shaft 7 and said plates alsohav- Iv

